<div dir="ltr">Thanks. That's a bug.<div><br></div><div style>uf-set-canonical! changes the canonical element of the set (without affecting the identity of the set).</div><div style><br></div><div style>Robby</div></div> <div class="gmail_extra"><br><br><div class="gmail_quote">On Tue, Jan 29, 2013 at 4:13 PM, Danny Yoo <span dir="ltr"><<a href="mailto:dyoo@hashcollision.org" target="_blank">dyoo@hashcollision.org</a>></span> wrote:<br> <blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex"><div class="im">On Tue, Jan 29, 2013 at 2:51 PM, Robby Findler<br> <<a href="mailto:robby@eecs.northwestern.edu">robby@eecs.northwestern.edu</a>> wrote:<br> > I've just pushed an implementation of the union-find algorithm to the data/<br> > collection. I didn't do it quite the way wikipedia recommends, but instead<br> > made the sets be little containers whose canonical element can be mutated.<br> <br> </div>Code reviewing...<br> <br> <br> I don't understand line 31 yet.<br> <br> <a href="http://git.racket-lang.org/plt/blob/33747ec9abc5f03d1b838aae11474351d5a6b534:/collects/data/union- find.rkt#l31" target="_blank">http://git.racket-lang.org/plt/blob/33747ec9abc5f03d1b838aae11474351d5a6b534:/collects/data/union-<br> find.rkt#l31</a><br> <br> <br> How can the rank decrease back to one? Isn't that supposed to be this instead?<br> <br> (set-uf-set-rank! a (add1 a-rank))<br> <br> <br> <br> I'm assuming that uf-set-x is either going to be another uf-set, or a<br> box. Is that right?<br> <br> <br> I do not understand what uf-set-canonical! is for yet; the test case<br> doesn't tell me too much.<br> </blockquote></div><br></div>